Salute all them that have the rule over you, and all the saints. They of Italy salute you (Hebrews 13:24).
The unknown author of the book of Hebrews (possibly the apostle Paul) was apparently writing from Italy, and thus could send a brotherly greeting from the Christians there to their fellow believers in Israel. The significant thing about this is that the members of the sending church were probably all Gentiles; in the receiving church they were all Jews.
The apostle Paul, once a Hebrew of the Hebrews (Philippians 3:5), detesting those outside the nation, had been transformed by the redeeming love of Christ into the apostle of the Gentiles (Romans 11:13).
It was necessary that the gospel be preached to the Jew first (Romans 1:16) and then unto the uttermost part of the earth (Acts 1:8). Although the first Christians, including the apostles and those to whom the book of Hebrews was written, were all Jews, it was not long before they being ignorant of Gods righteousness, and going about to establish their own righteousness, refused to submit themselves unto the righteousness of God (Romans 10:3), and returned to their ways of legalism. Thus, blindness in part is happened to Israel, until the fulness of the Gentiles be come in (Romans 11:25).
In the meantime, through Christ, both Jews and Gentiles have access by one Spirit unto the Father (Ephesians 2:18), for He hath made both one (Ephesians 2:14). Our text gives us a beautiful cameo of this new fellowship. Jewish Christians had gone all the way to Rome with the gospel and had won many of the Gentiles to their Christ. Now they of Italy, in turn, were saluting their new-found Jewish brethren, and encouraging them, through the apostolic writer who knew them all, to hold fast the profession of (their) faith without wavering (Hebrews 10:23). HMM